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<head>
  <meta charset="UTF-8">
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  <title>Document</title>
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<body>
  <script>
    // 数学运算符
    console.log(1 % 2);

    var aa = 1;
    aa += 1;//aa = aa + 1
    aa++;//aa = aa + 1
    console.log(aa);

    // 比较运算符(会返回一个布尔型的结果)


    console.log(false == 0);
    // console.log('hello' + ' word' + 666);
    // console.log('hello' - 'hello');

    // 与或非
    // console.log(true || 666);
    var cc = 888;
    var bb = cc || 999
    console.log('bb', bb);
    // if (null) {
    //   console.log('3>5');
    // } else {
    //   console.log('3<5');
    // }

  </script>
</body>

</html>